Additional research is needed to understand YA exposure to pro-tobacco and cannabis marketing across a wider range of marketing platforms. Further, tobacco products are marketed online largely via organic social media posts not labeled as advertising . Since respondents were asked generally about seeing ads “when using the internet,” we were unable to disentangle the various types of online marketing YA saw. Fifth, patterns of media consumption vary among YA , and heavy media users may recall more tobacco and cannabis marketing than light media users. While respondents were able indicate if they did not use the Internet or if they did not watch TV/movies at all, we were otherwise unable to account for the frequency or timing of their Internet or TV/ movie consumption. Sixth, these data are from a cohort of YA from Southern California, and so may not reflect national or regional trends in perceived marketing exposure. However, the sample was similar to population characteristics of Los Angeles, CA in terms of race/ethnicity and educational attainment . To reduce survey burden, respondents were not asked to report on all characteristics that may potentially be related to substance use . Finally, small sample sizes in some of the sociodemographic subgroups and in some of the specific products marketed resulted in wide confidence intervals on some of our estimates, and also precluded us from testing sociodemographic differences in viewing marketing across the various products. Binge drinking is mainly observed in adolescents and young adults, and concerns two thirds of college students in France . BD is usually defined as a pattern of alcohol consumption characterized by intermittent periods of heavy drinking over a short period of time and periods of abstinence .This specific pattern of consumption is frequently associated with the use of cannabis , which is the most consumed illicit substance in Europe, with 31% of French students reportedly having smoked it at least once in their lives .
Both BD and cannabis use have harmful consequences , making them a major public health issue. The focus must therefore be on BD and its association with cannabis use. The neuropsychological impairments induced by BD have been extensively documented in the scientific literature . This problematic drinking pattern can lead to brain atrophy in the prefrontal,vertical grow system temporal and parietal cortices, as well as in the hippocampus, inducing executive and memory disorders . BD mainly impairs executive functions, with increased impulsivity and a lack of cognitive control related to frontal dysfunction . Memory impairments have also been reported , but less consistently than executive disorders.Chronic cannabis consumption can also lead to brain damage, especially in hippocampal and prefrontal regions , resulting in episodic memory impairment and executive deficits . According to these studies, using cannabis in addition to BD leads to potentially more severe cognitive consequences. To sum up, the aforementioned studies describe common memory and executive impairments among BD and cannabis consumers. Although the cognitive deficits seem to be similar in nature, they appear to differ in severity, depending on which substance is used. Memory impairments are reported more than executive deficits in chronic cannabis users , with the opposite pattern for BD . Their combined use could therefore lead to memory and executive dysfunctions of the same severity, owing to an additive effect. Despite the frequency of alcohol and cannabis use among students, few studies have explored the additive effect of BD and cannabis use on neuropsychological deficits. To our knowledge, only two studies have so far been conducted among adolescents and young adults , and none with a sample made up solely of college students. Compared with young adults with a history of light and controlled substance use, poorer executive functioning and verbal episodic memory abilities have been observed in young BD and cannabis co-users. In Winward et al. ’s study, BD and cannabis co-use was associated with the executive and episodic memory impairments found in single-substance users , but co-users also had specific working memory impairments that are not observed in single users. Overall, these two studies suggest that the consumption of both substances has an additive effect on neuropsychological deficits, and encourage further research to examine co-use in college students and identify the characteristics of those who exhibit the poorest neuropsychological performances.
This knowledge is essential for designing appropriate prevention measures. Thus, for the first time in college students, the present study aimed to improve understanding of the additive effect of BD and cannabis use on neuropsychological functioning, and describe the profiles of student users who are at the greatest risk of neuropsychological deficits. Based on the literature, we first expected to observe executive and episodic memory deficits in college students who engage in BD, whether they smoked cannabis or not. Second, we expected to observe an additive effect of BD and cannabis use in students, resulting in more severe memory and executive function impairments than in BD students who did not consume cannabis. Finally, we expected to find a gradient of severity of neuropsychological impairments among BD students, with those who consumed cannabis grow equipment performing more poorly. Neuropsychological impairments were assessed with the Brief Evaluation of Alcohol-Related Neuropsychological Impairments . This test was specifically designed to screen for cognitive and motor deficits in patients with alcohol use disorders . It contains five subtests: verbal episodic memory , alphabetical span, assessing verbal working memory , alternating verbal fluency, assessing flexibility abilities , five complex figures, assessing visuospatial abilities , and ataxia, assessing balance . The BEARNI yields six scores: five subscores and a total score . The BEARNI is a screening tool that facilitates referral for a more detailed neuropsychological assessment. As low drinking does not lead to neuropsychological deficits, participants in the LD group with moderate impairments were excluded from the statistical analysis. First, participants’ raw BEARNI scores were transformed into z scores. A z score was computed for each BEARNI subtest, based on the mean and standard deviation of the LD group . Second, we calculated a linear mixed model, with BEARNI subtest z score as a within-participants variable, group as between-participants variable, and participant as a random component. Sex , age, Fagerstr¨om score, and BD score were included as covariates, to control for their effects.
Including these covariates allowed for a more precise assessment of the effects of our variable of interest on the BEARNI test, by providing estimated means of BEARNI subtests across the three groups, with the covariate effects in the model kept constant. To compare neuropsychological profiles between groups, we used the contrast method recommended by Cohen et al. . More specifically, we use two Helmert contrasts to test our hypotheses. The first contrast compared the LD group with the set of binge drinkers , thereby allowing us to test the overall effect of substance use on neuropsychological impairments . The second contrast compared the BD group with the BDC group, allowing us to assess the additive effect of BD and cannabis use on neuropsychological impairments . Regarding the hypotheses set out in the Introduction, we expected the LD group to perform better than both BD and BDC, with no difference between BD and BDC on executive functioning . As for memory, we expected LD to perform better than both BD and BDC, and BD to perform better than BDC . Finally, we further explored the heterogeneity of the users’ profiles by carrying out two analyses on the BD set . First, to examine the hypothesis of the additive effect in greater depth, we explored the distribution of the two groups’ executive and memory scores. Second, we performed a k-means clustering analysis including the BEARNI subscores. This revealed greater impairment in BDC than in BD. The algorithm was constrained to separate the users into two groups, and we assumed that one contained the less impaired profiles, and the other contained the more impaired profiles. This analysis allowed us to identify BD and BDC participants who were more or less cognitively impacted , and to pinpoint their specific characteristics regarding alcohol , tobacco , and cannabis consumption patterns, as well as anxiety and depression . The purpose of these analyses was thus to identify at-risk consumer profiles. We ran individual analyses to examine whether scores indicated a gradient of severity. We predicted that the BDC group would have more severe cognitive impairments than the BD group. Performances of BD and BDC participants on the BEARNI flexibility and episodic and working memory subtests were heterogeneous . Results showed a gradient of severity, specifically for the episodic memory subtest. Most BD participants had better scores than BDC, who performed more poorly, but the expected gradient was not found for working memory and flexibility subtests. The separation was not linear: BD and BDC overlapped on both the lowest and highest scores. A few BD participants performed more poorly than other BD, and some of the BDC had preserved performances when others had more severe impairments. This outcome encouraged us to go further to understand the factors that could explain the heterogeneity of cognitive performances found here. This was the first study to seek to improve understanding of the additive effect of college students’ BD and cannabis use on their neuropsychological functioning, and describe the profiles of student users who are most at risk of neuropsychological deficits.
Results showed that college students who engaged in binge drinking behavior with or without cannabis use performed consistently more poorly than LD on all the cognitive domains we assessed . An additive effect of BD and cannabis use was specifically observed on flexibility, episodic memory and working memory, when BD and BDC groups were contrasted. Individual analyses revealed heterogeneous gradients of cognitive impairment severity between BD and BDC. Finally, cluster analyses highlighted more severe neuropsychological deficits in users who frequently consumed tobacco and who had a high level of anxiety. The present study revealed negative effects of combined alcohol and cannabis use on episodic memory, executive functions, visuospatial skills, ataxia, and working memory in college students. With the exception of ataxia, this observation was in accordance with previous studies conducted among adolescents and young adults identified as BD or cannabis users . Ataxia is not usually described in BD, but is regularly reported in alcohol use disorder and cannabis use . We hypothesized that BD combined with cannabis use results in more severe memory and flexibility impairments, and results confirmed that BDC students did indeed have greater episodic memory, flexibility and working memory deficits than BD students. As shown in Winward et al. ’s study, combine use seemed to have a negative effect on working memory. However, contrary to their observations, we also found impaired working memory in BD without cannabis use. Flexibility and working memory abilities rely on the prefrontal cortex and cerebellum, which are rich in cannabinoid receptors, thus making them very sensitive to the neurotoxic effects of cannabis . Although other studies conducted in BD have not always clearly reported executive impairments encompassing flexibility and working memory abilities , cannabis use seems to heighten the negative effect of BD on executive functions. Moreover, the deleterious additive effect on episodic memory in the BDC group is consistent with the literature on chronic cannabis users , as well as with our hypothesis. This specific additive effect could be due to the peculiar neurotoxic effects of cannabis on the hippocampus . The hippocampus is a node of the brain network responsible for episodic memory abilities , and is rich in cannabinoid receptors . An additive effect on episodic memory could interfere with scores on flexibility and working memory subtests, as these are not purely executive tasks, but also rely on memory abilities. Further examination is needed, using executive tasks that do not involve memory, in order to disentangle the impact of these results. This study also deepened our understanding of the specific BDC neuropsychological profile in college students. Individual score analyses showed a gradient of severity, with a larger proportion of BDC students having poorer episodic memory performances than BD, despite greater heterogeneity than expected. Even among young students, this pattern indicates that adding cannabis consumption to BD mostly affects memory abilities. Together, these two products have an even more harmful effect on the developing brain than BD without cannabis . We expected this gradient of severity to be particularly marked for the working memory subtest, on which BDC performed more poorly overall than single-substance users, as reported by Winward et al. . Surprisingly, the gradient was more mixed and nonlinear for working memory and flexibility, but these subscores still indicated an additive effect of BD and cannabis use. These results point to a significant additive effect of cannabis when consumed with BD, although this does not necessarily lead to new additional impairments. Nevertheless, the present study highlighted heterogeneity, with some BD students having unexpectedly poor performances, and some BDC students having preserved performances. This prompted us to focus on variables that might help us identify the clinical profile of BD college students who are most at risk of developing neuropsychological impairment.